1. Field of the Disclosure
The present disclosure relates to a reciprocating compressor including a motor, and more particularly, to a reciprocating compressor that prevents reduced efficiency due to magnetic loss by reducing an amount of magnetic flux leaked to a cylinder from a stator through a frame and by inducing the leaked magnetic flux back to the motor.
2. Background
Generally, a reciprocating compressor serves to suck, compress, and discharge a refrigerant as a piston linearly reciprocates in a cylinder. The reciprocating compressor may be classified into a connection type reciprocating compressor and a vibration type reciprocating compressor according to a driving method of the piston. In the connection type reciprocating compressor, the piston reciprocates in the cylinder while connected to a connection rod which is connected to a rotation shaft of a rotation motor, thereby compressing the refrigerant. On the other hand, in the vibration type reciprocating compressor, the piston reciprocates in the cylinder and vibrates while connected with a mover of a reciprocating motor, thereby compressing a refrigerant. Hereinafter, for disclosure purposes only, the vibration type reciprocating compressor will be referred to as a reciprocating compressor in the passages below.
The reciprocating compressor usually comprises a reciprocating motor including an outer stator, an inner stator, and a mover that reciprocates and is disposed between the two stators; a cylinder inserted into the inner stator of the reciprocating motor and fixed to a frame, or fixedly inserted into the inner stator; a piston coupled to the mover, for compressing a refrigerant while the mover reciprocates in the cylinder; and resonant springs disposed at front and rear sides of the piston, for inducing a relative motion of the piston with respect to the cylinder by resonating a reciprocation of the reciprocating motor. A suction passage for passing sucked refrigerant is formed in the piston. A suction valve is disposed at the end of the suction passage (or the piston), and a discharge valve is disposed at the fore end of the cylinder.
In the conventional reciprocating compressor, as the piston reciprocates with respect to the cylinder using a driving force generated by the reciprocating motor, the refrigerant is sucked, compressed, and then discharged. The above process is repeatedly performed.
In the conventional reciprocating motor, the frame is formed of aluminum, a non-magnetic substance to minimize a leakage amount of magnetic flux. However, since aluminum has conductivity, magnetic flux may be leaked to the cylinder due to eddy current of the frame. Accordingly, the efficiency of the reciprocating motor and the reciprocating compressor having the same may be lowered.